1
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Arnold BH, Sanislav O, Fisher PR, Annesley SJ. Plate-Based Assays for the Characterization of Mitochondrial and Cellular Phenotypes. Methods Mol Biol 2024; 2746:1-20. [PMID: 38070076 DOI: 10.1007/978-1-0716-3585-8_1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2023]
Abstract
The mitochondria are essential to eukaryotic life, acting as key drivers of energy generation while also being involved in the regulation of many cellular processes including apoptosis, cell proliferation, calcium homeostasis, and metabolism. Mitochondrial diseases which disrupt these processes lead to a diverse range of pathologies and lack consistency in symptom presentation. In disease, mitochondrial activity and energy homeostasis can be adapted to cellular requirements, and studies using Dictyostelium and human lymphoblastoid cell lines have shown that such changes can be facilitated by the key cellular and energy regulators, TORC1 and AMPK. Fluorescence-based assays are increasingly utilized to measure mitochondrial and cell signalling function in mitochondrial disease research. Here, we describe a streamlined method for the simultaneous measurement of mitochondrial mass, membrane potential, and reactive oxygen species production using MitoTracker Green™ FM, MitoTracker Red™ CMXRos, and DCFH-DA probes. This protocol has been adapted for both Dictyostelium and human lymphoblastoid cell lines. We also describe a method for assessing TORC1 and AMPK activity simultaneously in lymphoblastoid cells. These techniques allow for the characterization of mitochondrial defects in a rapid and easy to implement manner.
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Affiliation(s)
- Benjamin Henry Arnold
- Department of Microbiology, Anatomy, Physiology and Pharmacology, La Trobe University, Melbourne, VIC, Australia
| | - Oana Sanislav
- Department of Microbiology, Anatomy, Physiology and Pharmacology, La Trobe University, Melbourne, VIC, Australia
| | - Paul Robert Fisher
- Department of Microbiology, Anatomy, Physiology and Pharmacology, La Trobe University, Melbourne, VIC, Australia
| | - Sarah Jane Annesley
- Department of Microbiology, Anatomy, Physiology and Pharmacology, La Trobe University, Melbourne, VIC, Australia.
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2
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Flores-Leon M, Outeiro TF. More than meets the eye in Parkinson's disease and other synucleinopathies: from proteinopathy to lipidopathy. Acta Neuropathol 2023; 146:369-385. [PMID: 37421475 PMCID: PMC10412683 DOI: 10.1007/s00401-023-02601-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2023] [Revised: 06/12/2023] [Accepted: 06/14/2023] [Indexed: 07/10/2023]
Abstract
The accumulation of proteinaceous inclusions in the brain is a common feature among neurodegenerative diseases such as Alzheimer's disease, Parkinson's disease (PD), and dementia with Lewy bodies (DLB). The main neuropathological hallmark of PD and DLB are inclusions, known as Lewy bodies (LBs), enriched not only in α-synuclein (aSyn), but also in lipid species, organelles, membranes, and even nucleic acids. Furthermore, several genetic risk factors for PD are mutations in genes involved in lipid metabolism, such as GBA1, VSP35, or PINK1. Thus, it is not surprising that mechanisms that have been implicated in PD, such as inflammation, altered intracellular and vesicular trafficking, mitochondrial dysfunction, and alterations in the protein degradation systems, may be also directly or indirectly connected through lipid homeostasis. In this review, we highlight and discuss the recent evidence that suggests lipid biology as important drivers of PD, and which require renovated attention by neuropathologists. Particularly, we address the implication of lipids in aSyn accumulation and in the spreading of aSyn pathology, in mitochondrial dysfunction, and in ER stress. Together, this suggests we should broaden the view of PD not only as a proteinopathy but also as a lipidopathy.
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Affiliation(s)
- Manuel Flores-Leon
- Department of Experimental Neurodegeneration, Center for Biostructural Imaging of Neurodegeneration, University Medical Center Göttingen, 37073, Göttingen, Germany
- Facultad de Ciencias, Universidad Nacional Autónoma de México, Ciudad Universitaria, Ciudad de México, Mexico
| | - Tiago Fleming Outeiro
- Department of Experimental Neurodegeneration, Center for Biostructural Imaging of Neurodegeneration, University Medical Center Göttingen, 37073, Göttingen, Germany.
- Max Planck Institute for Multidisciplinary Science, Göttingen, Germany.
- Faculty of Medical Sciences, Translational and Clinical Research Institute, Newcastle University, Framlington Place, Newcastle Upon Tyne, NE2 4HH, UK.
- Scientific Employee with an Honorary Contract at Deutsches Zentrum für Neurodegenerative Erkrankungen (DZNE), Göttingen, Germany.
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3
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Cable J, Witwer KW, Coffey RJ, Milosavljevic A, von Lersner AK, Jimenez L, Pucci F, Barr MM, Dekker N, Barman B, Humphrys D, Williams J, de Palma M, Guo W, Bastos N, Hill AF, Levy E, Hantak MP, Crewe C, Aikawa E, Adamczyk AM, Zanotto TM, Ostrowski M, Arab T, Rabe DC, Sheikh A, da Silva DR, Jones JC, Okeoma C, Gaborski T, Zhang Q, Gololobova O. Exosomes, microvesicles, and other extracellular vesicles-a Keystone Symposia report. Ann N Y Acad Sci 2023; 1523:24-37. [PMID: 36961472 PMCID: PMC10715677 DOI: 10.1111/nyas.14974] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/20/2023]
Abstract
Extracellular vesicles (EVs) are small, lipid-bilayer-bound particles released by cells that can contain important bioactive molecules, including lipids, RNAs, and proteins. Once released in the extracellular environment, EVs can act as messengers locally as well as to distant tissues to coordinate tissue homeostasis and systemic responses. There is a growing interest in not only understanding the physiology of EVs as signaling particles but also leveraging them as minimally invasive diagnostic and prognostic biomarkers (e.g., they can be found in biofluids) and drug-delivery vehicles. On October 30-November 2, 2022, researchers in the EV field convened for the Keystone symposium "Exosomes, Microvesicles, and Other Extracellular Vesicles" to discuss developing standardized language and methodology, new data on the basic biology of EVs and potential clinical utility, as well as novel technologies to isolate and characterize EVs.
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Affiliation(s)
| | - Kenneth W Witwer
- Department of Molecular and Comparative Pathobiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Robert J Coffey
- Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Aleksandar Milosavljevic
- Department of Molecular and Human Genetics; Dan L Duncan Comprehensive Cancer Center; and Program in Quantitative and Computational Biosciences, Baylor College of Medicine, Houston, Texas, USA
| | | | - Lizandra Jimenez
- Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
| | - Ferdinando Pucci
- Department of Otolaryngology-Head and Neck Surgery; Department of Cell, Developmental & Cancer Biology; Knight Cancer Institute, Oregon Health & Science University, Portland, Oregon, USA
| | - Maureen M Barr
- Department of Genetics and Human Genetics Institute of New Jersey, Rutgers, The State University of New Jersey, Piscataway, New Jersey, USA
| | - Niek Dekker
- Protein Sciences, Discovery Sciences, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Bahnisikha Barman
- Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
| | | | - Justin Williams
- University of California, Berkeley, Berkeley, California, USA
| | - Michele de Palma
- Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Swiss Federal Institute of Technology in Lausanne (EPFL); Agora Cancer Research Center; and Swiss Cancer Center Léman (SCCL), Lausanne, Switzerland
| | - Wei Guo
- Department of Biology, School of Arts & Sciences, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Nuno Bastos
- i3S Instituto de Investigação e Inovação em Saúde; IPATIMUP Institute of Molecular Pathology and Immunology; and ICBAS Instituto de Ciencias Biomédicas Abel Salazar, University of Porto, Porto, Portugal
| | - Andrew F Hill
- Research Centre for Extracellular Vesicles; Department of Biochemistry and Chemistry, School of Agriculture, Biomedicine and Environment, La Trobe University and Institute for Health and Sport, Victoria University, Melbourne, Victoria, Australia
| | - Efrat Levy
- Center for Dementia Research, Nathan S. Kline Institute for Psychiatric Research, Orangeburg, New York, USA
- Department of Psychiatry; Department of Biochemistry & Molecular Pharmacology; and NYU Neuroscience Institute, New York University Grossman School of Medicine, New York, New York, USA
| | - Michael P Hantak
- Department of Neurobiology and Anatomy, University of Utah, Salt Lake City, Utah, USA
| | - Clair Crewe
- Touchstone Diabetes Center, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, USA
- Department of Cell Biology, Washington University, St. Louis, Missouri, USA
| | - Elena Aikawa
- Center for Interdisciplinary Cardiovascular Sciences, Division of Cardiovascular Medicine and Center for Excellence in Vascular Biology, Department of Medicine; Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | | | - Tamires M Zanotto
- Section of Integrative Physiology and Metabolism, Joslin Diabetes Center, Harvard Medical School, Boston, Massachusetts, USA
| | - Matias Ostrowski
- Facultad de Medicina, Instituto de Investigaciones Biomédicas en Retrovirus y Sida (INBIRS), Universidad de Buenos Aires (UBA) and Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
| | - Tanina Arab
- Department of Molecular and Comparative Pathobiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Daniel C Rabe
- Mass General Cancer Center, Harvard Medical School, Charlestown, Massachusetts, USA
| | - Aadil Sheikh
- Department of Biology, College of Arts and Sciences, Baylor University, Waco, Texas, USA
| | | | - Jennifer C Jones
- Translational Nanobiology Section, Laboratory of Pathology and Vaccine Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - Chioma Okeoma
- Department of Pharmacology, Stony Brook University Renaissance School of Medicine, Stony Brook, New York, USA
- Department of Pathology, Microbiology, and Immunology, New York Medical College, Valhalla, New York, USA
| | - Thomas Gaborski
- School of Chemistry and Materials Science, Rochester Institute of Technology, Rochester, New York, USA
| | - Qin Zhang
- Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Olesia Gololobova
- Department of Molecular and Comparative Pathobiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
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4
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Annesley SJ, Allan CY, Sanislav O, Evans A, Fisher PR. Dysregulated Gene Expression in Lymphoblasts from Parkinson’s Disease. Proteomes 2022; 10:proteomes10020020. [PMID: 35736800 PMCID: PMC9230639 DOI: 10.3390/proteomes10020020] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Revised: 05/19/2022] [Accepted: 05/20/2022] [Indexed: 02/01/2023] Open
Abstract
Parkinson’s disease is the second largest neurodegenerative disease worldwide and is caused by a combination of genetics and environment. It is characterized by the death of neurons in the substantia nigra of the brain but is not solely a disease of the brain, as it affects multiple tissues and organs. Studying Parkinson’s disease in accessible tissues such as skin and blood has increased our understanding of the disease’s pathogenesis. Here, we used lymphoblast cell lines generated from Parkinson’s disease patient and healthy age- and sex-matched control groups and obtained their whole-cell transcriptomes and proteomes. Our analysis revealed, in both the transcriptomes and the proteomes of PD cells, a global downregulation of genes involved in protein synthesis, as well as the upregulation of immune processes and sphingolipid metabolism. In contrast, we discovered an uncoupling of mRNA and protein expression in processes associated with mitochondrial respiration in the form of a general downregulation in associated transcripts and an upregulation in proteins. Complex V was different to the other oxidative phosphorylation complexes in that the levels of its associated transcripts were also lower, but the levels of their encoded polypeptides were not elevated. This may suggest that further layers of regulation specific to Complex V are in play.
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Affiliation(s)
- Sarah Jane Annesley
- Department of Microbiology, Anatomy, Physiology and Pharmacology, La Trobe University, Melbourne, VIC 3086, Australia; (C.Y.A.); (O.S.); (P.R.F.)
- Correspondence: ; Tel.: +61-394791412
| | - Claire Yvonne Allan
- Department of Microbiology, Anatomy, Physiology and Pharmacology, La Trobe University, Melbourne, VIC 3086, Australia; (C.Y.A.); (O.S.); (P.R.F.)
| | - Oana Sanislav
- Department of Microbiology, Anatomy, Physiology and Pharmacology, La Trobe University, Melbourne, VIC 3086, Australia; (C.Y.A.); (O.S.); (P.R.F.)
| | - Andrew Evans
- Department of Neurology, Royal Melbourne Hospital, Parkville, VIC 3052, Australia;
| | - Paul Robert Fisher
- Department of Microbiology, Anatomy, Physiology and Pharmacology, La Trobe University, Melbourne, VIC 3086, Australia; (C.Y.A.); (O.S.); (P.R.F.)
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5
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Storey CL, Williams RSB, Fisher PR, Annesley SJ. Dictyostelium discoideum: A Model System for Neurological Disorders. Cells 2022; 11:cells11030463. [PMID: 35159273 PMCID: PMC8833889 DOI: 10.3390/cells11030463] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 01/23/2022] [Accepted: 01/24/2022] [Indexed: 12/14/2022] Open
Abstract
Background: The incidence of neurological disorders is increasing due to population growth and extended life expectancy. Despite advances in the understanding of these disorders, curative strategies for treatment have not yet eventuated. In part, this is due to the complexities of the disorders and a lack of identification of their specific underlying pathologies. Dictyostelium discoideum has provided a useful, simple model to aid in unraveling the complex pathological characteristics of neurological disorders including Alzheimer’s disease, Parkinson’s disease, Huntington’s disease, neuronal ceroid lipofuscinoses and lissencephaly. In addition, D. discoideum has proven to be an innovative model for pharmaceutical research in the neurological field. Scope of review: This review describes the contributions of D. discoideum in the field of neurological research. The continued exploration of proteins implicated in neurological disorders in D. discoideum may elucidate their pathological roles and fast-track curative therapeutics.
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Affiliation(s)
- Claire Louise Storey
- Department of Microbiology, Anatomy, Physiology and Pharmacology, La Trobe University, Bundoora 3086, Australia; (C.L.S.); (P.R.F.)
| | - Robin Simon Brooke Williams
- Centre for Biomedical Sciences, School of Biological Sciences, Royal Holloway University of London, Egham TW20 0EX, UK;
| | - Paul Robert Fisher
- Department of Microbiology, Anatomy, Physiology and Pharmacology, La Trobe University, Bundoora 3086, Australia; (C.L.S.); (P.R.F.)
| | - Sarah Jane Annesley
- Department of Microbiology, Anatomy, Physiology and Pharmacology, La Trobe University, Bundoora 3086, Australia; (C.L.S.); (P.R.F.)
- Correspondence: ; Tel.: +61-394-791-412
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6
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Nuclear and cytoplasmic huntingtin inclusions exhibit distinct biochemical composition, interactome and ultrastructural properties. Nat Commun 2021; 12:6579. [PMID: 34772920 PMCID: PMC8589980 DOI: 10.1038/s41467-021-26684-z] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Accepted: 10/11/2021] [Indexed: 12/20/2022] Open
Abstract
Despite the strong evidence linking the aggregation of the Huntingtin protein (Htt) to the pathogenesis of Huntington's disease (HD), the mechanisms underlying Htt aggregation and neurodegeneration remain poorly understood. Herein, we investigated the ultrastructural properties and protein composition of Htt cytoplasmic and nuclear inclusions in mammalian cells and primary neurons overexpressing mutant exon1 of the Htt protein. Our findings provide unique insight into the ultrastructural properties of cytoplasmic and nuclear Htt inclusions and their mechanisms of formation. We show that Htt inclusion formation and maturation are complex processes that, although initially driven by polyQ-dependent Htt aggregation, also involve the polyQ and PRD domain-dependent sequestration of lipids and cytoplasmic and cytoskeletal proteins related to HD dysregulated pathways; the recruitment and accumulation of remodeled or dysfunctional membranous organelles, and the impairment of the protein quality control and degradation machinery. We also show that nuclear and cytoplasmic Htt inclusions exhibit distinct biochemical compositions and ultrastructural properties, suggesting different mechanisms of aggregation and toxicity.
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7
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Mroczek K, Fernando S, Fisher PR, Annesley SJ. Interactions and Cytotoxicity of Human Neurodegeneration- Associated Proteins Tau and α-Synuclein in the Simple Model Dictyostelium discoideum. Front Cell Dev Biol 2021; 9:741662. [PMID: 34552934 PMCID: PMC8450459 DOI: 10.3389/fcell.2021.741662] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Accepted: 08/19/2021] [Indexed: 11/17/2022] Open
Abstract
The abnormal accumulation of the tau protein into aggregates is a hallmark in neurodegenerative diseases collectively known as tauopathies. In normal conditions, tau binds off and on microtubules aiding in their assembly and stability dependent on the phosphorylation state of the protein. In disease-affected neurons, hyperphosphorylation leads to the accumulation of the tau protein into aggregates, mainly neurofibrillary tangles (NFT) which have been seen to colocalise with other protein aggregates in neurodegeneration. One such protein is α-synuclein, the main constituent of Lewy bodies (LB), a hallmark of Parkinson's disease (PD). In many neurodegenerative diseases, including PD, the colocalisation of tau and α-synuclein has been observed, suggesting possible interactions between the two proteins. To explore the cytotoxicity and interactions between these two proteins, we expressed full length human tau and α-synuclein in Dictyostelium discoideum alone, and in combination. We show that tau is phosphorylated in D. discoideum and colocalises closely (within 40 nm) with tubulin throughout the cytoplasm of the cell as well as with α-synuclein at the cortex. Expressing wild type α-synuclein alone caused inhibited growth on bacterial lawns, phagocytosis and intracellular Legionella proliferation rates, but activated mitochondrial respiration and non-mitochondrial oxygen consumption. The expression of tau alone impaired multicellular morphogenesis, axenic growth and phototaxis, while enhancing intracellular Legionella proliferation. Direct respirometric assays showed that tau impairs mitochondrial ATP synthesis and increased the "proton leak," while having no impact on respiratory complex I or II function. In most cases depending on the phenotype, the coexpression of tau and α-synuclein exacerbated (phototaxis, fruiting body morphology), or reversed (phagocytosis, growth on plates, mitochondrial respiratory function, Legionella proliferation) the defects caused by either tau or α-synuclein expressed individually. Proteomics data revealed distinct patterns of dysregulation in strains ectopically expressing tau or α-synuclein or both, but down regulation of expression of cytoskeletal proteins was apparent in all three groups and most evident in the strain expressing both proteins. These results indicate that tau and α-synuclein exhibit different but overlapping patterns of intracellular localisation, that they individually exert distinct but overlapping patterns of cytotoxic effects and that they interact, probably physically in the cell cortex as well as directly or indirectly in affecting some phenotypes. The results show the efficacy of using D. discoideum as a model to study the interaction of proteins involved in neurodegeneration.
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Affiliation(s)
| | | | | | - Sarah J. Annesley
- Department of Physiology, Anatomy and Microbiology, La Trobe University, Bundoora, VIC, Australia
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8
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Chen S, Annesley SJ, Jasim RAF, Fisher PR. The Parkinson's Disease-Associated Protein DJ-1 Protects Dictyostelium Cells from AMPK-Dependent Outcomes of Oxidative Stress. Cells 2021; 10:cells10081874. [PMID: 34440642 PMCID: PMC8392454 DOI: 10.3390/cells10081874] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Revised: 07/17/2021] [Accepted: 07/22/2021] [Indexed: 01/24/2023] Open
Abstract
Mitochondrial dysfunction has been implicated in the pathology of Parkinson’s disease (PD). In Dictyostelium discoideum, strains with mitochondrial dysfunction present consistent, AMPK-dependent phenotypes. This provides an opportunity to investigate if the loss of function of specific PD-associated genes produces cellular pathology by causing mitochondrial dysfunction with AMPK-mediated consequences. DJ-1 is a PD-associated, cytosolic protein with a conserved oxidizable cysteine residue that is important for the protein’s ability to protect cells from the pathological consequences of oxidative stress. Dictyostelium DJ-1 (encoded by the gene deeJ) is located in the cytosol from where it indirectly inhibits mitochondrial respiration and also exerts a positive, nonmitochondrial role in endocytosis (particularly phagocytosis). Its loss in unstressed cells impairs endocytosis and causes correspondingly slower growth, while also stimulating mitochondrial respiration. We report here that oxidative stress in Dictyostelium cells inhibits mitochondrial respiration and impairs phagocytosis in an AMPK-dependent manner. This adds to the separate impairment of phagocytosis caused by DJ-1 knockdown. Oxidative stress also combines with DJ-1 loss in an AMPK-dependent manner to impair or exacerbate defects in phototaxis, morphogenesis and growth. It thereby phenocopies mitochondrial dysfunction. These results support a model in which the oxidized but not the reduced form of DJ-1 inhibits AMPK in the cytosol, thereby protecting cells from the adverse consequences of oxidative stress, mitochondrial dysfunction and the resulting AMPK hyperactivity.
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Affiliation(s)
- Suwei Chen
- Discipline of Microbiology, Department of Physiology Anatomy and Microbiology, School of Life Sciences, La Trobe University, Bundoora, VIC 3086, Australia; (S.C.); (S.J.A.); (R.A.F.J.)
- School of Modern Agriculture and Biotechnology, Ankang University, Ankang 725000, China
| | - Sarah J. Annesley
- Discipline of Microbiology, Department of Physiology Anatomy and Microbiology, School of Life Sciences, La Trobe University, Bundoora, VIC 3086, Australia; (S.C.); (S.J.A.); (R.A.F.J.)
| | - Rasha A. F. Jasim
- Discipline of Microbiology, Department of Physiology Anatomy and Microbiology, School of Life Sciences, La Trobe University, Bundoora, VIC 3086, Australia; (S.C.); (S.J.A.); (R.A.F.J.)
- Department of Laboratory and Clinical Sciences, College of Pharmacy, University of Babylon, Hillah 51002, Iraq
| | - Paul R. Fisher
- Discipline of Microbiology, Department of Physiology Anatomy and Microbiology, School of Life Sciences, La Trobe University, Bundoora, VIC 3086, Australia; (S.C.); (S.J.A.); (R.A.F.J.)
- Correspondence: ; Tel.: +61-3-9479-2229
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9
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Annesley SJ, Fisher PR. Lymphoblastoid Cell Lines as Models to Study Mitochondrial Function in Neurological Disorders. Int J Mol Sci 2021; 22:4536. [PMID: 33926115 PMCID: PMC8123577 DOI: 10.3390/ijms22094536] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Revised: 04/23/2021] [Accepted: 04/24/2021] [Indexed: 12/12/2022] Open
Abstract
Neurological disorders, including neurodegenerative diseases, are collectively a major cause of death and disability worldwide. Whilst the underlying disease mechanisms remain elusive, altered mitochondrial function has been clearly implicated and is a key area of study in these disorders. Studying mitochondrial function in these disorders is difficult due to the inaccessibility of brain tissue, which is the key tissue affected in these diseases. To overcome this issue, numerous cell models have been used, each providing unique benefits and limitations. Here, we focussed on the use of lymphoblastoid cell lines (LCLs) to study mitochondrial function in neurological disorders. LCLs have long been used as tools for genomic analyses, but here we described their use in functional studies specifically in regard to mitochondrial function. These models have enabled characterisation of the underlying mitochondrial defect, identification of altered signalling pathways and proteins, differences in mitochondrial function between subsets of particular disorders and identification of biomarkers of the disease. The examples provided here suggest that these cells will be useful for development of diagnostic tests (which in most cases do not exist), identification of drug targets and testing of pharmacological agents, and are a worthwhile model for studying mitochondrial function in neurological disorders.
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Affiliation(s)
- Sarah Jane Annesley
- Department of Physiology, Anatomy and Microbiology, La Trobe University, Bundoora, VIC 3086, Australia;
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10
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Falabella M, Vernon HJ, Hanna MG, Claypool SM, Pitceathly RDS. Cardiolipin, Mitochondria, and Neurological Disease. Trends Endocrinol Metab 2021; 32:224-237. [PMID: 33640250 PMCID: PMC8277580 DOI: 10.1016/j.tem.2021.01.006] [Citation(s) in RCA: 113] [Impact Index Per Article: 37.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Revised: 01/26/2021] [Accepted: 01/27/2021] [Indexed: 02/07/2023]
Abstract
Over the past decade, it has become clear that lipid homeostasis is central to cellular metabolism. Lipids are particularly abundant in the central nervous system (CNS) where they modulate membrane fluidity, electric signal transduction, and synaptic stabilization. Abnormal lipid profiles reported in Alzheimer's disease (AD), Parkinson's disease (PD), amyotrophic lateral sclerosis (ALS), and traumatic brain injury (TBI), are further support for the importance of lipid metablism in the nervous system. Cardiolipin (CL), a mitochondria-exclusive phospholipid, has recently emerged as a focus of neurodegenerative disease research. Aberrant CL content, structure, and localization are linked to impaired neurogenesis and neuronal dysfunction, contributing to aging and the pathogenesis of several neurodegenerative diseases, such as AD and PD. Furthermore, the highly tissue-specific acyl chain composition of CL confers it significant potential as a biomarker to diagnose and monitor the progression in several neurological diseases. CL also represents a potential target for pharmacological strategies aimed at treating neurodegeneration. Given the equipoise that currently exists between CL metabolism, mitochondrial function, and neurological disease, we review the role of CL in nervous system physiology and monogenic and neurodegenerative disease pathophysiology, in addition to its potential application as a biomarker and pharmacological target.
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Affiliation(s)
- Micol Falabella
- Department of Neuromuscular Diseases, University College London Queen Square Institute of Neurology, London, UK
| | - Hilary J Vernon
- Department of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Michael G Hanna
- Department of Neuromuscular Diseases, University College London Queen Square Institute of Neurology and The National Hospital for Neurology and Neurosurgery, London, UK
| | - Steven M Claypool
- Department of Physiology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Robert D S Pitceathly
- Department of Neuromuscular Diseases, University College London Queen Square Institute of Neurology and The National Hospital for Neurology and Neurosurgery, London, UK.
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11
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Ugalde CL, Gordon SE, Shambrook M, Nasiri Kenari A, Coleman BM, Perugini MA, Lawson VA, Finkelstein DI, Hill AF. An intact membrane is essential for small extracellular vesicle-induced modulation of α-synuclein fibrillization. J Extracell Vesicles 2020; 10:e12034. [PMID: 33318779 PMCID: PMC7726797 DOI: 10.1002/jev2.12034] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Revised: 10/09/2020] [Accepted: 11/08/2020] [Indexed: 01/05/2023] Open
Abstract
The misfolding and fibrillization of the protein, α-synuclein (αsyn), is associated with neurodegenerative disorders referred to as the synucleinopathies. Understanding the mechanisms of αsyn misfolding is an important area of interest given that αsyn misfolding contributes to disease pathogenesis. While many studies report the ability of synthetic lipid membranes to modulate αsyn folding, there is little data pertaining to the mechanism(s) of this interaction. αSyn has previously been shown to associate with small lipid vesicles released by cells called extracellular vesicles (EVs) and it is postulated these interactions may assist in the spreading of pathological forms of this protein. Together, this presents the need for robust characterisation studies on αsyn fibrillization using biologically-derived vesicles. In this study, we comprehensively characterised the ability of lipid-rich small extracellular vesicles (sEVs) to alter the misfolding of αsyn induced using the Protein Misfolding Cyclic Amplification (PMCA) assay. The biochemical and biophysical properties of misfolded αsyn were examined using a range of techniques including: Thioflavin T fluorescence, transmission electron microscopy, analytical centrifugation and western immunoblot coupled with protease resistance assays and soluble/insoluble fractionation. We show that sEVs cause an acceleration in αsyn fibrillization and provide comprehensive evidence that this results in an increase in the abundance of mature insoluble fibrillar species. In order to elucidate the relevance of the lipid membrane to this interaction, sEV lipid membranes were modified by treatment with methanol, or a combination of methanol and sarkosyl. These treatments altered the ultrastructure of the sEVs without changing the protein cargo. Critically, these modified sEVs had a reduced ability to influence αsyn fibrillization compared to untreated counterparts. This study reports the first comprehensive examination of αsyn:EV interactions and demonstrates that sEVs are powerful modulators of αsyn fibrillization, which is mediated by the sEV membrane. In doing so, this work provides strong evidence for a role of sEVs in contributing directly to αsyn misfolding in the synucleinopathy disorders.
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Affiliation(s)
- Cathryn L. Ugalde
- La Trobe Institute of Molecular ScienceLa Trobe UniversityBundooraVictoriaAustralia
- Howard Florey Institute of Neuroscience and Mental HealthParkvilleVictoriaAustralia
- Department of Microbiology and ImmunologyUniversity of MelbourneParkvilleVictoriaAustralia
- Department of Biochemistry and Molecular BiologyUniversity of MelbourneParkvilleVictoriaAustralia
| | - Shane E. Gordon
- La Trobe Institute of Molecular ScienceLa Trobe UniversityBundooraVictoriaAustralia
| | - Mitch Shambrook
- La Trobe Institute of Molecular ScienceLa Trobe UniversityBundooraVictoriaAustralia
| | | | - Bradley M. Coleman
- Department of Biochemistry and Molecular BiologyUniversity of MelbourneParkvilleVictoriaAustralia
| | - Matthew A. Perugini
- La Trobe Institute of Molecular ScienceLa Trobe UniversityBundooraVictoriaAustralia
| | - Victoria A. Lawson
- Department of Microbiology and ImmunologyUniversity of MelbourneParkvilleVictoriaAustralia
| | - David I. Finkelstein
- Howard Florey Institute of Neuroscience and Mental HealthParkvilleVictoriaAustralia
| | - Andrew F. Hill
- La Trobe Institute of Molecular ScienceLa Trobe UniversityBundooraVictoriaAustralia
- Department of Biochemistry and Molecular BiologyUniversity of MelbourneParkvilleVictoriaAustralia
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Fernando S, Allan CY, Mroczek K, Pearce X, Sanislav O, Fisher PR, Annesley SJ. Cytotoxicity and Mitochondrial Dysregulation Caused by α-Synuclein in Dictyostelium discoideum. Cells 2020; 9:E2289. [PMID: 33066427 PMCID: PMC7602147 DOI: 10.3390/cells9102289] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Revised: 10/09/2020] [Accepted: 10/12/2020] [Indexed: 12/13/2022] Open
Abstract
Alpha synuclein has been linked to both sporadic and familial forms of Parkinson's disease (PD) and is the most abundant protein in Lewy bodies a hallmark of Parkinson's disease. The function of this protein and the molecular mechanisms underlying its toxicity are still unclear, but many studies have suggested that the mechanism of α-synuclein toxicity involves alterations to mitochondrial function. Here we expressed human α-synuclein and two PD-causing α-synuclein mutant proteins (with a point mutation, A53T, and a C-terminal 20 amino acid truncation) in the eukaryotic model Dictyostelium discoideum. Mitochondrial disease has been well studied in D. discoideum and, unlike in mammals, mitochondrial dysfunction results in a clear set of defective phenotypes. These defective phenotypes are caused by the chronic hyperactivation of the cellular energy sensor, AMP-activated protein kinase (AMPK). Expression of α-synuclein wild type and mutant forms was toxic to the cells and mitochondrial function was dysregulated. Some but not all of the defective phenotypes could be rescued by down regulation of AMPK revealing both AMPK-dependent and -independent mechanisms. Importantly, we also show that the C-terminus of α-synuclein is required and sufficient for the localisation of the protein to the cell cortex in D. discoideum.
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Affiliation(s)
| | | | | | | | | | | | - Sarah J. Annesley
- Department of Physiology, Anatomy and Microbiology, La Trobe University, Bundoora 3086, Melbourne, Australia; (S.F.); (C.Y.A.); (K.M.); (X.P.); (O.S.); (P.R.F.)
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Gilmozzi V, Gentile G, Castelo Rueda MP, Hicks AA, Pramstaller PP, Zanon A, Lévesque M, Pichler I. Interaction of Alpha-Synuclein With Lipids: Mitochondrial Cardiolipin as a Critical Player in the Pathogenesis of Parkinson's Disease. Front Neurosci 2020; 14:578993. [PMID: 33122994 PMCID: PMC7573567 DOI: 10.3389/fnins.2020.578993] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Accepted: 09/10/2020] [Indexed: 12/31/2022] Open
Abstract
Alpha-Synuclein (α-Syn) is a central protein in the pathogenesis of synucleinopathies, a group of neurodegenerative disorders including Parkinson’s disease (PD). Although its role in neurotransmission is well established, the precise role of this protein in disease pathogenesis is still not fully understood. It is, however, widely regarded to be associated with the misfolding and accumulation of toxic intracellular aggregates. In fact, α-Syn is the most abundant protein component of Lewy bodies and Lewy neurites, which are also characterized by a high lipid content. Lipids, the main constituents of cellular membranes, have been implicated in many aspects of PD-related processes. α-Syn interacts with membrane phospholipids and free fatty acids via its N-terminal domain, and altered lipid-protein complexes might enhance both its binding to synaptic and mitochondrial membranes and its oligomerization. Several studies have highlighted a specific interaction of α-Syn with the phospholipid cardiolipin (CL), a major constituent of mitochondrial membranes. By interacting with CL, α-Syn is able to disrupt mitochondrial membrane integrity, leading to mitochondrial dysfunction. Additionally, externalized CL is able to facilitate the refolding of toxic α-Syn species at the outer mitochondrial membrane. In this review, we discuss how α-Syn/lipid interactions, in particular the α-Syn/CL interaction at the mitochondrial membrane, may affect α-Syn aggregation and mitochondrial dysfunction and may thus represent an important mechanism in the pathogenesis of PD.
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Affiliation(s)
- Valentina Gilmozzi
- Institute for Biomedicine, Eurac Research, Affiliated Institute of the University of Lübeck, Bolzano, Italy
| | - Giovanna Gentile
- Institute for Biomedicine, Eurac Research, Affiliated Institute of the University of Lübeck, Bolzano, Italy
| | | | - Andrew A Hicks
- Institute for Biomedicine, Eurac Research, Affiliated Institute of the University of Lübeck, Bolzano, Italy
| | - Peter P Pramstaller
- Institute for Biomedicine, Eurac Research, Affiliated Institute of the University of Lübeck, Bolzano, Italy.,Department of Neurology, University of Lübeck, Lübeck, Germany
| | - Alessandra Zanon
- Institute for Biomedicine, Eurac Research, Affiliated Institute of the University of Lübeck, Bolzano, Italy
| | - Martin Lévesque
- Department of Psychiatry and Neurosciences, Cervo Brain Research Centre, Université Laval, Quebec, QC, Canada
| | - Irene Pichler
- Institute for Biomedicine, Eurac Research, Affiliated Institute of the University of Lübeck, Bolzano, Italy
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First person – Cathryn Ugalde. Dis Model Mech 2020. [PMCID: PMC6994923 DOI: 10.1242/dmm.043919] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
ABSTRACT
First Person is a series of interviews with the first authors of a selection of papers published in Disease Models & Mechanisms, helping early-career researchers promote themselves alongside their papers. Cathryn Ugalde is first author on ‘Misfolded α-synuclein causes hyperactive respiration without functional deficit in live neuroblastoma cells’, published in DMM. Cathryn is a postdoctoral research scientist in the lab of Prof. Andrew Hill at La Trobe University, Bundoora, Australia, investigating neurodegeneration associated with protein misfolding.
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